LED lighting may generally provide advantages in energy conservation, environmental protection, controllable lighting, solid state lighting, and long operational lifetime. LED lamps thus have been widely used in various areas for public, commercial, and/or indoor lightings.
Often, LED lamps may have lamp-head structures designed similar to incandescent lamps, energy saving lamps, and other conventional lamps. Presumably, LED lamps may be used to replace other conventional lamps by an easy installation without changing original structures of a lighting system including other conventional lamps. However, existing LED power and control circuits are integrated circuits and the structures are very complicated. For the LED power and control circuits formed by discrete components, a master switch often may be a triode. The control device of the master switch may also be a triode. In general, the working temperature of the LED lamps is relatively high. Therefore, the disadvantages of this control mode may include large temperature drifts, unstable output electrical currents of the LED, and low efficiencies.
The disclosed LED power circuit using discrete components and configuration methods are directed to solve one or more problems set forth above and other problems.